Compression vest for patients undergoing hemodialysis and in critical care

ABSTRACT

A method of inhibiting hypotensive symptoms in a patient undergoing treatment or a procedure involves elastically constraining the internal organs within the abdomen of the patient while applying non-pulsating, compressive pressure to the internal organs within the abdomen of the patient. The method may also involve one or more of infusing fluid, applying the compressive pressure using compression device, or applying the compressive pressure based upon bio-indicator measurement parameters.

CROSS-REFERENCE TO RELATED APPLICATION

This application is continuation-in-part of U.S. patent application Ser.No. 12/977,574, filed Dec. 23, 2010 (now issued as U.S. Pat. No.9,155,541), which, in turn, is a continuation-in-part of U.S. patentapplication Ser. No. 12/062,944, filed April 4, 2008 (now issued as U.S.Pat. No. 7,879,069), which, in turn, claims the priority benefit of U.S.Provisional Patent Application No. 61/000,436, filed Oct. 26, 2007, thedisclosures of each of these applications are incorporated herein byreference in their entirety.

FIELD

This application relates generally to medical devices and procedures,and more particularly, to medical devices, procedures and treatmentsused during hemodialysis or on a critical care patient.

BACKGROUND

Patients suffering from renal failure of the kidneys are often treatedusing hemodialysis procedures to remove excess fluid and metabolicwastes (e.g., urea, creatinine, etc.) accumulated in body tissue andblood. During hemodialysis, a patient's blood is shunted from the bodythrough a hemodialysis machine for diffusion and ultrafiltration beforebeing returned to the patient's circulation system. Hemodialysistreatments are typically performed three or perhaps four times per weekon a patient having chronic renal failure, with each session lastingbetween three to five hours.

Patients undergoing hemodialysis treatment are prone to suffer fromhypotensive (low blood pressure) symptoms, such as headache, dizziness,muscle cramping and vomiting. Despite the many improvements made tomodern hemodialysis procedures, intradialytic hypotension inhemodialysis patients continues to be a major source of concern for thewell being of the patient. Many hemodialysis patients experience chronichypotension, which is abnormal decrease in the patients' blood pressure.For some of these patients, the intradialytic hypotensive symptoms areso severe that they cannot tolerate the hemodialysis procedure and mustinstead resort to peritoneal dialysis or renal transplant. Indeed,repeated development of these hypotensive symptoms is a key factorleading to the high mortality rate of hemodialysis patients.

For many hemodialysis patients, it is believed that the intradialytichypotensive symptoms result from the pooling of blood within theinternal organs in the abdominal area or waist of the hemodialysispatient. Some have proposed use of an inflatable abdominal band toimprove orthostatic hypotension, which is associated with a decrease insystolic blood pressure when patients change from supine to standingposition. For instance, N. Yamamoto et al., Treatment of post-dialyticorthostatic hypotension with an inflatable abdominal band inhemodialysis patients, KIDNEY INTERNATIONAL, 70:1793-1800 (Sep. 27,2006), discloses use of an inflatable abdominal band to treat patients,who after their hemodialysis treatment, are suffering from post-dialyticorthostatic hypotension. H. Tanaka et al., Treatment of orthostaticintolerance with inflatable abdominal band, THE LANCET, 349:175 (Jan.18, 1997), discloses use of an inflatable abdominal band to treatorthostatic hypotension in patients with orthostatic intolerance. A.Smit et al., Use of lower abdominal compression to combat orthostatichypotension in patients with autonomic dysfunction, CLIN AUTON RES14:167-175 (2004), discloses use of an elastic abdominal binding toincrease standing blood pressure in patients with neurogenic orthostatichypotension. J. Deng et al., Efficacy of compression of differentcapacitance beds in the amelioration of orthostatic hypotension,CLINICAL AUTONOMIC RESEARCH 7, 321-326 (1997), discloses use ofcompression garments such as an antigravity suit (G suit) in treatingpatients with chronic symptomatic orthostatic hypotension.

Other types of compressive devices are known in the art. For instance,U.S. Pat. No. 4,925,133 entitled “Hydraulic Buoyancy Force Suit”discloses a buoyancy force suit to reduce pooling of blood with the goalof maintaining consciousness of flying pilots. U.S. Pat. No. 4,534,338entitled “Servo Operated Anti-G Suit Pressurization System” discloses aservo operated system for quickly pressurizing an aircraft pilot'santi-G suit during high energy maneuvers. U.S. Pat. No. 4,938,208entitled “Full Length Compressible Sleeve” discloses a sleeve forapplying compressive pressure against a patient's limb to preventpooling of blood in a patient's limb. Similarly, arterial pressuresphygmomanometers include an inflatable compression band worn about apatient's arm to identify diastolic and systolic arterial pressure.Non-inflatable work wear or belts that wrap around a person's waist areused to reduce the load on the back by providing additional support forthe spine.

None of these references, however, address treatment of intradialytichypotension occurring during the hemodialysis treatment. It is,therefore, desirable to reduce the pooling of blood in the abdominalorgans of the patient during hemodialysis treatments in order toeliminate the development of intradialytic hypotensive symptoms over thecourse of hemodialysis.

Patients in critical care may also encounter similar problems resultingfrom trauma or burns. Reducing the pooling of blood in the abdominalorgans of such critical care patients can lead to more effective fluidand blood infusion and improve cardiac filling to enhance cardiovascularfunctions of these seriously ill patients. Therefore, it is alsodesirable to reduce the pooling of blood in the abdominal organs ofcritical care patients to make fluid or blood infusion more effective inimproving cardiac filling to enhance cardiovascular functions.

SUMMARY

One aspect of the disclosure involves a method of increasing venousreturn in a hypotensive patient in critical care suffering from blood orfluid loss. The method involves elastically constraining the abdomen ofthe patient while a) concurrently maintaining mobility of the patient'slegs and applying non-pulsating compressive pressure to the internalorgans within the abdomen of the patient according to a predefinedprotocol, and b) infusing a volume of fluid into the patient'sbloodstream, such that pooling of blood within the patient's abdominalinternal organs and distribution of the infused volume in the abdominalorgans are both reduced.

Another aspect of the disclosure involves a method of inhibitinghypotensive symptoms in a patient undergoing a procedure. The methodinvolves elastically constraining the abdomen of the patient throughoutthe procedure while concurrently maintaining mobility of the patient'slegs; and applying non-pulsating compressive pressure to the internalorgans within the abdomen of the patient during the procedure with anelastic vest having multiple discrete elastic bands affixed thereto,each of the discrete elastic bands having a free end wherein the totalnumber of free ends comprises at least three free ends, the elastic vestincluding multiple markings thereon to denote compression levels thatwill be applied when the free ends are releasably affixed to the elasticvest near the markings, the constraining thereby reducing the pooling ofblood within the patient's abdominal internal organs while concurrentlyallowing for unencumbered movement of the patient's legs during theprocedure.

Yet another aspect of the disclosure involves a further method ofinhibiting hypotensive symptoms in a patient undergoing a procedure. Themethod involves elastically constraining the abdomen of the patientthroughout the procedure while concurrently maintaining mobility of thepatient's legs and applying non-pulsating, compressive pressure to theinternal organs within the abdomen of the patient according to apredefined protocol during the procedure, the protocol includingmonitoring bioimpedance of the abdominal organs of the patient, thepatient's blood density and hematocrit, thereby reducing the pooling ofblood within the patient's abdominal internal organs while concurrentlyallowing for unencumbered movement of the patient's legs during theprocedure.

Yet another aspect of this disclosure involves a method of treating ahypotensive patient undergoing a treatment. The method involveselastically constraining the abdomen of the patient while a)concurrently maintaining mobility of the patient's legs and applyingnon-pulsating compressive pressure to the internal organs within theabdomen of the patient according to a predefined protocol, and b)infusing a volume of fluid into the patient's bloodstream, such thatpooling of blood within the patient's abdominal internal organs anddistribution of the infused volume to the abdominal organs are bothreduced.

Yet another aspect of this disclosure involves a further method oftreating a hypotensive patient undergoing a treatment. The methodinvolves elastically constraining the abdomen of the patient whileconcurrently maintaining mobility of the patient's legs and applyingnon-pulsating, compressive pressure to the internal organs within theabdomen of the patient according to a predefined protocol while thetreatment is in progress. The protocol includes monitoring one or morebio-indicator measurement parameters and applying the compressivepressure based upon the bio-indicator measurement parameters, therebyinhibiting the hypotensive symptoms while concurrently allowing forunencumbered movement of the patient's legs while the treatment is inprogress.

These aspects and advantages arising from the present disclosure will beapparent to those of ordinary skill in the art by reference to thefollowing detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example compression/anti-pooling vest worn aroundthe waist of a patient in accordance with the present disclosure;

FIG. 1A illustrates the dial of a pressure gauge utilized with thecompression vest illustrated in FIG. 1;

FIG. 2 is a plan view of the inner surface of one example embodiment ofthe compression vest illustrated in FIG. 1;

FIG. 2A is a perspective view illustrating the outer surface of thecompression vest shown in FIG. 2;

FIG. 3 is a plan view of the inner surface of another example embodimentof the compression vest;

FIG. 3A is a perspective view illustrating the outer surface of thecompression vest shown in FIG. 3;

FIG. 4 illustrates an inflatable bladder utilized with the compressionvest illustrated in FIG. 1;

FIG. 4A illustrates the configuration of the inflatable bladder, tubing,manual pressurization system and pressure gauge utilized with thecompression vest illustrated in FIG. 1;

FIG. 5 is a graph illustrating manual pressurization of the compressionvest over time during a hemodialysis treatment;

FIG. 6 is a schematic diagram of an automatic pressurization controllerfor pressurizing or depressurizing the inflatable bladder of thecompression vest;

FIG. 7 illustrates an example display on an automatic pressurizationcontroller for the compression vest;

FIG. 8 is a graph illustrating pressurization of the compression vestover time by an automatic pressurization controller during ahemodialysis treatment;

FIG. 9 is a plan view of the inner surface of a further exampleembodiment of the compression vest;

FIG. 9A is a perspective view illustrating the outer surface of thecompression vest of FIG. 9;

FIG. 10 is a simplified view of an optional pad and its cross sectionthat can be inserted into an optional pocket of the compression vest;

FIG. 11 is a simplified view of yet an additional alternativeimplementation of a compression vest as described herein.

DETAILED DESCRIPTION

An anti-pooling/compression wear or vest 10 is disclosed herein forpreventing the pooling of blood or other fluids in the organs within theabdomen or waist of a patient. The vest 10 may be used for a variety ofmedical purposes, including, but not limited to, countering thedevelopment of intradialytic hypotensive symptoms in patients undergoinghemodialysis and/or improving cardiac filling to enhance cardiovascularfunctions in critical care patients suffering from trauma or burns. Asused herein, the terms “treatment” and “procedure” are usedinterchangeably and intended to interchangeably mean any or all of theseas well as dealing with or preventing hypotensive symptoms in general.This disclosure also includes methods and protocols to pressurize thepatient's abdominal organs to one or more preset or predeterminedpressures during and after the treatment, designs of the vest 10 tobest-fit patient's abdominal contour, and safety features of the vest 10for the patient's well being.

Vest With Manual Operation

FIG. 1 illustrates an example of the anti-pooling/compression wear orvest 10 worn around the waist or abdomen of a patient. The vest 10includes a flexible band 20 and an inflatable bladder 30 with tubing 32that may be pressurized using a manual pressurization system 40. Anautomatic pressurization system, such as the system described furtherbelow and illustrated in FIGS. 6-8, may be substituted for the manualpressurization system 40.

A patient is illustrated in FIG. 1 squeezing a manual pump or bulb 40 toincrease pressure in the inflatable bladder 30, which is located withinthe vest 10. The pressure within the inflatable bladder 30 is displayedon a pressure dial or gauge 50, which is shown in FIG. 1 as being heldin the patient's other hand. A dial 50 a of the pressure gauge 50 isillustrated in FIG. 1A. The dial 50 a includes a plurality of markingsindicative of pressure in, for example, mm Hg, with a region 52 a of themarkings being highlighted to indicate that pressure above a preset orpredetermined maximum threshold (e.g., above 30 mm Hg) for use with theanti-pooling vest 10. To ensure proper use of the vest 10, instructionlabels may be provided on the vest 10, as well as a nametag for thepatient and/or health care professional to write the patient's name.

One example embodiment of the band 20 is illustrated in FIGS. 2 and 2A.The band 20 is flexible so that it can be wrapped about the abdomen orwaist of the patient. The band 20 is typically made of nylon, such as,for example, polyurethane coated 420d Nylon fabric (420D/PU2 Nylon).Alternatively, the band 20 may be made from other suitablenon-stretchable fabrics. The band 20 may be, for example, approximatelyeight to ten inches wide and approximately 55 inches in length. The sizeof the band, its material and its color may be modified to fit the needor preference of the patient.

The inner or back surface 20 a of the band 20 is illustrated in FIG. 2.This is the surface 20 a that contacts the patient when the band 20 iswrapped about the abdomen or waist of the patient as illustrated inFIG. 1. A webbing trim 22, such as, for example, a ⅞ inch polypropylene(PP) webbing trim, may be provided around the edges of the band 20. Theinner surface 20 a of the band 20 includes an area 23 provided with aplurality of fasteners, such as Velcro® brand hook fasteners, forreleasably engaging corresponding fasteners, such as Velcro® brand loops24 a, 24 b, located on the front surface 20 b of the band 20.

The front or outer surface 20 b of the band 20 is illustrated in FIG.2A. The outer surface 20 b is the surface of the band 20 that is exposedwhen the band is wrapped about the abdomen or waist of a patient asillustrated in FIG. 1. The outer surface 20 b includes an area 24 a, 24b containing a plurality of fasteners, such as Velcro® brand loops. Whenthe band 20 is wrapped about the abdomen or waist of a patient with theinner surface 20 a in contact with the patient as is shown in FIG. 1,the band may be releasably held in place by bringing the area 23containing the plurality of hook fasteners into contact with thecorresponding loops in the area 24 a on the outer surface 20 b of theband. It is understood that the arrangement of hook and loop fastenersmay be reversed so that the loop fasteners are arranged in area 23 andthe hook fasteners in area 24 a, 24 b.

The band 20 also includes one or more elastic bands or strips 25, 26,each strip having one end that is sewn or otherwise affixed to the outersurface 20 b of the band 20 and an opposing end that is free from theouter surface. A fastener 25 a, 26 a, such as one part of a Velcro®brand hook and loop fastener, is connected to the free end of each ofthe elastic strips 25, 26. Each elastic strip 25, 26 is between about1.75 and about 3 inches wide. In the embodiment illustrated in FIGS. 2and 2A, the band 20 includes three spaced apart, elastic strips 25having their free end with the fastener 25 a extending in the directionof area 24 a and three spaced apart, elastic strips 26 having their freeend with the fastener 26 a extending in the direction of area 24 b. Theuse of three pairs of elastic strips 25, 26 makes the band 20 moreclosely conform to the body contour of the patient for more effectivecompression of internal organs and provides a greater safety margin forthe patient not to be overly compressed. It is understood, however, thatthe use of three pairs of elastic strips 25, 26 is exemplary and thatthe band may incorporate a greater number or lesser number of elasticstrips 25, 26 than illustrated in the drawings.

As discussed above, the band 20 is first wrapped about the abdomen orwaist of a patient to enclose most of the patient's internal organs. Theband 20 is releasably held in place by bringing the area 23 containingthe plurality of hook fasteners into contact with the correspondingloops in the area 24 a on the outer surface 20 b of the band. To betterconform the band 20 to the contour of the patient's waist, the free endof each elastic strip 25 is stretched in the direction of area 24 a andthe free end of each elastic strip 26 is stretched in the direction ofarea 24 b. When sufficient tension is placed on each strip to betterconform the band 20 to the contour of patient's waist, then the elasticstrips 25, 26 are releasably connected to the band by engaging the hookfasteners 25 a, 26 a on the free ends of the strips with thecorresponding loop fasteners located in the areas 24 a and 24 b on theouter surface 20 b of the band.

The band 20 also may include a pouch or pocket 27 having an opening 27 athrough which the inflatable bladder 30 inserted for placement withinthe pocket 27. Alternatively, the inflatable bladder 30 may be anintegral part or otherwise built into the band 20. In this embodiment,the opening 27 a is approximately five inches in length and the pocket27 is approximately 19 inches in length to accommodate a 16 inch byseven inch inflatable bladder 30. The inside of the pocket 27 istypically made from nylon, such as, for example, polyurethane coated 210d Nylon fabric (210D/PU2 Nylon). When the vest 10 is properly fitted onthe patient and the inflatable bladder 30 in the pocket 27 ispressurized, the elastic straps 25, 26 and Velcro® brand hook and loopfasteners ensure uniform pressure compression of the patient's internalorgans.

Another example embodiment of the band 20′ is illustrated in FIGS. 3 and3A. The band 20′ is similar to the band 20 illustrated in FIGS. 2 and2A, with the exception that two strips 23 a, 23 b of fasteners, such asVelcro® brand hook fasteners, are provided in the area 23. These strips23 a, 23 b may be affixed to the band 20′ in a conventional manner, suchas, for example, by sewing and/or using an adhesive. When the band 20′is wrapped about the abdomen or waist of a patient with the innersurface 20 a in contact with the patient as is shown in FIG. 1, the bandmay be releasably held in place by bringing the two strips 23 a, 23 b ofhook fasteners into contact with the corresponding loops in the area 24a on the outer surface 20 b of the band. The construction and operationof the band 20′ is similar to the band 20 described above in all othermaterial respects.

An example inflatable bladder 30 is illustrated in FIG. 4. The bladder30 is typically made of flexible polyvinyl chloride (PVC), rubber orother impermeable materials that can be inflated without air leakage. Asdiscussed above, the bladder 30 is inserted through the opening 27 a inthe band 20, 20′ to fit snugly to the pocket 27. Alternatively, thebladder 30 may be an integral part or otherwise built into the band 20.The bladder 30 may be, for example, a PVC sheet of 16 inches by fourteenfolded to form a dimension of 16 inches by seven inches with three sidesheat sealed. Other configurations of the bladder 30 may also be usedwith the anti-pooling vest 10. Hollow, flexible tubing 32 extends fromthe bladder 30 to provide a fluid conduit to the pressurization system,pressure gauge and optional alarm.

FIG. 4A illustrates an exemplary configuration of the inflatable bladder30, tubing 32, manual pressurization system 40 and pressure gauge 50utilized with the vest 10. The manual pressurization system includes abulb or manual pump 40, a pressure release valve 40 a, a pressure gauge50, and an optional alarm (not shown). As illustrated in FIG. 1, thetubing 32 from the inflatable bladder 30 is joined through a T-joint orother connector to the tubing 32 connected to the bulb 40 and pressuregauge 50. The functions of these components are described next.

When the pressure release control valve 40 a of the bulb or manual pump40 is set to the closed position, the repeated hand squeeze of the bulbby the patient or health care professional causes the bladder 30 toinflate to a predetermined, preset or desired pressure level asindicated by the pressure gauge 50. By turning the control valve 40 a tothe open position, the pressurized air in bladder 30 is released and thepressure in the bladder can return to zero. A one-way control valve 40 bat the distal opening or air inlet of the bulb 40 only permits ambientair to enter the bulb 40 and flow from the bulb 40 as it is squeezedthrough the pressure release control valve 40 a to inflate the bladder30. When the bulb 30 is relaxed and returns to its normal configuration,air is allowed to flow through the one-way valve 40 b from theatmosphere to fill up the bulb.

The pressure gauge 50 displays the pressure in the bladder 30, whichcorresponds to the pressure being imposed on the internal organs of thepatient when the anti-pooling vest 10 is worn by the patient. A safetypressure release valve (not shown) may be incorporated into the pressuregauge 50 or elsewhere in the pressurization system to limit the maximumpressure that can be imposed by the anti-pooling vest 10 on thepatient's waist and internal organs. Normally, the maximum pressure toinflate the bladder 30 would not exceed 20 mm Hg. Accordingly, thesafety pressure release valve could be set to automatically open andrelease pressure in the bladder 30 that exceeds, for example, 30 mm Hgor 40 mm Hg.

An optional alarm may also be used with the vest 10 to make an audiblesound at preset or predetermined time intervals to remind the healthcare professional and/or patient that it may be time to adjust theinflation pressure of the bladder 30 according to, for example, thepressurization protocols described herein.

Manual Pressurization And Depressurization Protocol

Prior to starting the hemodialysis treatment, the vest 10 is placedabout the abdomen or waist of the patient in the manner described above.Once the hemodialysis process is initiated with the patient, one courseof pressurization of the inflatable bladder 30 will be a step increaseof the pressure by about 3 to 5 mm Hg every half an hour of treatment.

Two illustrative examples of manual pressurization protocols areillustrated in FIG. 5. The first manual pressurization protocolillustrated in FIG. 5 is for a hemodialysis treatment period ofapproximately 2.5 hours. Prior to commencing hemodialysis treatment, thebladder 30 worn about the patient's abdomen or waist is inflated to apredetermined or preset pressure of about 5 mm Hg by manually squeezingthe bulb or pump 40 and the pressure is maintained at this level forabout 30 minutes. The pressure in the bladder 30 is then increased to asecond predetermined or preset pressure of about 9 mm Hg by manuallysqueezing the bulb or pump 40 and maintained at this level for about 30minutes. After about an hour of treatment, the pressure in the bladder30 is again increased to a third predetermined or preset pressure ofabout 12 mm Hg by manually squeezing the bulb or pump 40 and maintainedat this level for another 30 minutes. After about 1.5 hours oftreatment, the pressure in the bladder 30 is again increased to a fourthpredetermined or preset pressure of about 16 mm Hg by manually squeezingthe bulb or pump 40 and maintained at this level for 30 minutes. Afterabout two hours of treatment, the pressure in the bladder 30 isincreased to a fifth predetermined or preset pressure of about 20 mm Hgby manually squeezing the bulb or pump 40 and maintained at thispressure until the 2.5 hour treatment is completed. Once the 2.5 hourtreatment period is completed, the patient continues to wear thepressurized anti-pooling vest 10 for at least 30 minutes to an hour.During this time, the pressure in the bladder 30 is gradually reduced tozero using the pressure relief valve 40 a to allow the blood volume inthe patient's internal organs to gradually return to desirable levelswithout hypotension. Thereafter, the depressurized vest 10 may beremoved from the patient.

The second manual pressurization protocol illustrated in FIG. 5 is for ahemodialysis treatment period of approximately three hours. Prior tocommencing hemodialysis treatment, the bladder 30 worn about thepatient's abdomen or waist is inflated to a predetermined or presetpressure of about 5 mm Hg by manually squeezing the bulb or pump 40 andthe pressure is maintained at this level for about 30 minutes. Thepressure in the bladder 30 is then increased to a second predeterminedor preset pressure of about 7.5 mm Hg by manually squeezing the bulb orpump 40 and maintained at this level for about 30 minutes. After aboutan hour of treatment, the pressure in the bladder 30 is again increasedto a third predetermined or preset pressure of about 10 mm Hg bymanually squeezing the bulb or pump 40 and maintained at this level foranother 30 minutes. After about 1.5 hours of treatment, the pressure inthe bladder 30 is again increased a fourth predetermined or presetpressure of to about 12.5 mm Hg by manually squeezing the bulb or pump40 and maintained at this level for 30 minutes. After about two hours oftreatment, the pressure in the bladder 30 is increased to a fifthpredetermined or preset pressure of about 15 mm Hg by manually squeezingthe bulb or pump 40 and maintained at this pressure for 30 minutes.After about 2.5 hours of treatment, the pressure in the bladder 30 isagain increased to a sixth predetermined or preset pressure of about17.5 mm Hg by manually squeezing the bulb or pump 40 and maintained atthis level for 30 minutes. After about three hours of treatment, thepressure in the bladder 30 is increased to a seventh predetermined orpreset pressure of about 20 mm Hg by manually squeezing the bulb or pump40 and maintained at this pressure until the 3.5 hour treatment iscompleted. Once the 3.5 hour treatment period is completed, the patientcontinues to wear the pressurized vest 10 for at least 30 minutes to anhour. During this time, the pressure in the bladder 30 is graduallyreduced to zero using the pressure relief valve 40 a to allow the bloodvolume in the patient's internal organs to gradually return to desirablelevels without hypotension. Thereafter, the depressurized vest 10 may beremoved from the patient.

Vest With Automatic Operation

The vest 10 may also be utilized with an automatic, programmablepressurization/depressurization system. A schematic diagram of anexample automatic, programmable system for pressurizing ordepressurizing the inflatable bladder 30 of the vest 10 is illustratedin FIG. 6. The bladder 30 in the vest 10 may be inflated topredetermined, preset or desired pressures during and after thetreatment in accordance with pressurization/depressurization protocolsthat correspond to the length of treatment and maximum desired pressurethat have been selected by the physician and/or health careprofessional. The band 20, 20′ and inflatable bladder 30 in the vestwith automatic operation is identical in all material respects to thatof the vest 10 described above with manual operation.

In the example embodiment illustrated in FIG. 6, the inflatable bladder30 in the vest 10 worn about the patient's abdomen or waist is connectedby tubing or conduit 32 to an air pump 350, a depressurization valve310, and a pressure sensor/gauge 300. A four way joint, pipe connectoror other conventional fitting 360 may be utilized to facilitate fluidconnection of the pump 350, depressurization valve 310, and pressuresensor/gauge 300. The pump 350 is an electric pump that is powered by apump power supply 320 and capable of generating sufficient air pressureto inflate the bladder 30 to the desired inflation pressure. When thepump 350 and depressurization valve 310 are not activated, nocommunication occurs between the joint 360 and atmosphere. For increasedsafety to ensure that the patient is not overly compressed by theautomatic pressurization system, the pump 350 and its associated powersupply 320 should have the characteristic that the maximum deliverablepressure at zero flow is less than a preset or predetermined value.

The automatic pressurization/depressurization system also includes acontroller 100 for controlling the pump 350 (and associatedpressurization of the bladder 30) and the depressurization valve 310 toautomatically achieve the desired pressurization/depressurizationprotocol, which will be discussed below with respect to FIG. 8. Thecontroller 100 includes a processor 200 (e.g., central processing unit(“CPU”), a memory 205 (e.g., random access memory (“RAM”) and/or readonly memory (“ROM”)), and a storage device 210 (e.g., hard disk drive,compact disk drive, etc.). Various input/output devices are connected tothe processor 200, such as a display 115, start switch 105, timer 110,treatment period setting switch 120, maximum pressure setting switch125, and pressure sensor/gauge 300.

A display 115 on the automatic pressurization controller 100 for thevest 10 is illustrated in FIG. 7. The controller 100 includes a startswitch 105, treatment period setting switch 120, and maximum pressuresetting switch 125. The physician or health care professional canactivate the controller 100 and turn power on to all units in thecontroller by depressing the start switch 105.

Prior to starting the hemodialysis treatment using the automaticpressurization system, the vest 10 is placed about the abdomen or waistof the patient in the manner described above. The physician or otherhealth care professional can select the treatment period forpressurization of the inflation bladder 30 by moving the selector switch120 to the desired time interval (e.g., 2.5 hours, 3.0 hours, 3.5 hours,etc.). Similarly, the physician or other health care professional canselect the maximum pressure to inflate the bladder 30 by moving theselector switch 125 to the desired maximum pressure (e.g., 15 mm Hg, 20mm Hg, 30 mm Hg, etc.). It is understood that the number and value ofthe selector switch positions illustrated in FIG. 7 are exemplary andthat this disclosure is not intended to be limited to the specificswitch or a specific number of positions and/or values associated withthose positions illustrated in the drawings.

The processor 200 is pre-programmed with apressurization/depressurization protocol for each combination of timeinterval and maximum pressure settings of the switches 120, 125.Exemplary pressurization/depressurization protocols are discussedfurther below with respect to FIG. 8.

The display 115 displays the current time, the time in treatment T, andthe actual measured pressure P in the inflatable bladder 30 as measuredby the pressure sensor/gauge 300. The timer 110 keeps the current timeand records the time in treatment T, which information is communicatedto the processor 200 and is also displayed on the display 115.

The processor 200 derives the pressure P in the inflatable bladder 30(without the oscillation associated with respiration) by averaging thepressure output from the pressure sensor/gauge 300. This ensures thatpressure fluctuation due to the patient's breathing is removed. Thepressure sensor/gauge 300 measures the actual pressure P in theinflatable bladder 30 and sends a signal associated with the measuredpressure P to the processor 200 to determine when to activate the pump350 and/or depressurization valve 310. The processor 200 executes thepre-programmed pressurization/depressurization protocol to adjust thepressure P in the inflatable bladder 30 based on the elapsed treatmenttime T input from the timer 110, the actual pressure P input from thepressure sensor/gauge 300, and the selected treatment period and maximumpressure settings from the switches 120, 125.

If the actual pressure P measured by the pressure sensor/gauge 300 isbelow the desired pressure, as determined by the pre-programmed pressureprotocol, then the processor 200 activates the pump power supply 320 todrive the pump 350 to inflate the bladder 30. When the actual pressure Pmeasured by the pressure sensor/gauge 300 reaches the desired pressureaccording to the pressure protocol, then the processor 200 deactivatesthe pump power supply 320 to turn the power off to the pump 350. As asafety feature, the voltage from the power supply 320 can be limited tonot exceed a predetermined or preset voltage so that the pressuregenerated by the pump 350 cannot exceed a predetermined or presetpressure threshold, which is typically a maximum pressure P of 30 mm Hg.

When the elapsed treatment time T measured by the timer 110 exceeds thepreset treatment time according to the selected setting of the switch120, the processor 200 activates the depressurization valve 310 bytransmitting a signal to the solenoid on the depressurization valve toopen the valve and slowly depressurize the inflatable bladder 30 byventing or otherwise releasing air from the bladder to atmosphere.

Four exemplary automatic pressurization/depressurization protocols areillustrated in FIG. 8 to show the time course of the pressure to inflatethe bladder 30 and thus to generate compression to the patient'sabdominal organs. The four exemplary protocols are for a selectedmaximum pressure of 20 mm Hg for hemodialysis treatment times of 2.5hours, three hours, 3.5 hours and four hours, respectively. Theprotocols illustrate a predetermined or preset increase inpressurization of the inflatable bladder 30 over time up to the maximumdesired pressure and then the gradual decrease in pressure in theinflatable bladder for at least 30 minutes following the expiration ofthe hemodialysis treatment time. It is understood that the predeterminedor preset inflation pressures correspond to the length of treatment andmaximum desired pressure selected by the physician or other health careprofessional.

A higher compression pressure will reduce the blood volume in thepatient's abdominal organs for the improvement of venous return, whichwill subsequently increase cardiac filling and cardiac output for thealleviation of hypotensive symptoms.

Because the improved venous return will lead to better cardiac fillingand subsequently higher cardiac output, the improved cardiovascularfunctions may allow the physician to prescribe a higher rate ofultrafiltration for the patient during the course of hemodialysis. Inthis way, the hemodialysis treatment time may be reduced for the removalof the same volume of excess fluid that had been accumulated in the bodytissue over the time between the previous hemodialysis treatment and thecurrent one.

Once the patient completes the hemodialysis treatment, the patient wouldstill wear the anti-pooling vest for the depressurization process. Thisprocess will allow the patient's cardiovascular system to adjust to thedepressurization and to minimize the potential for blood to rapidly poolback to the abdominal organs and subsequently the development ofhypotensive symptoms.

The physician could also prescribe the use of vest 10 for homehemodialysis. Its use can shorten the time required to complete homehemodialysis and to reduce the incidence on the development ofhypotensive symptoms.

Operation of the Vest for Patients with Trauma or Burns in Hospital'sCritical Care Units

Because of blood or fluid loss though trauma or burns, these patientsare often hypotensive and require infusion of a volume of fluid orblood. Some of the infused fluid or blood volume tends to expand themicrocirculation and/or the macrocirculation. It is the latter thatwould determine the filling of the heart chambers. More cardiac fillingwould enable the non-damaged heart to increase cardiac output to delivermore blood flow to important organs. With better blood flow, the patienthas a better and speedier chance for recovery. During the hypotensivestage, whether in trauma or during hemodialysis, blood vessels mayautoregulate for dilatation to allow more blood to flow through thevessel. Advantageously, use of the vest 10 in conjunction with infusioncan be used to improve cardiac filling and make the volume expansionmore effective for the alleviation of hypotension and/or shock.

Contrary to conventional thinking, this combination approach treats theabdominal organs as being the reason why fluid infusion alone is lesseffective in countering hypovolemia, hypotension and low cardiac output.Thus, the physician may prescribe the use of the vest 10 for patientscapable of accepting abdominal compression to counter the dilatation ofblood vessels within the internal organs within the waist or abdomen ofthe patient for the improvement of venous return during fluid infusion.As a result, the infused blood volume would become more effective toincrease venous return, cardiac filling and subsequently cardiac outputfor the betterment of cardiovascular functions in critical care patientsand patients in shock. Similarly, fluid infusion can be used duringhemodialysis if the use of the vest 10 alone cannot adequately mitigatethe intradialytic hypotension. Thus, by infusing a volume of fluid intothe patient's bloodstream while the vest 10 is applying compressivepressure to the patient's abdominal internal organs, pooling of bloodwithin the patient's abdominal internal organs and distribution of theinfused volume in the abdominal organs will both be reduced.

A low arterial pressure or low total blood volume is an indication ofpoor cardiovascular function. The larger the pressurization to beprovided by the anti-pooling vest, the greater the shifting of bloodfrom the internal organs toward the heart. Accordingly, the physicianmay select the level of pressurization to be inversely proportional toeither the arterial blood pressure or the total blood volume of thepatient.

The physician may order the use of appropriate medication, such as theuse of vasoconstrictor eye drops or intra-muscle injection, to furthercomplement the anti-pooling function of the vest 10.

Non-Inflatable Configurations

Another alternative example embodiment of the vest includes analternative band 20″ as illustrated in FIGS. 9 and 9A. This exampleembodiment of the band 20″ is not inflatable and is, or includesportions, that are stretchably elastic so that it can be wrapped aboutthe abdomen or waist of the patient and different degrees of stretch canbe used to apply differing levels of compressive force to the internalabdominal organs.

In order to accommodate different size and girth people, the band 20″can be provided in different sizes. Table 1 below shows representativeexample dimensions for the band to accommodate different sized people.It is believed that four sizes should be sufficient for most instances,however, it should be understood that a greater or lesser number ofsizes can be used. Note that the columns labeled “a,” “b,” “c,” “d” and“h”” correspond to the similarly labeled dimensions in FIGS. 9 and 9A(not to scale) with the distances under column “a” denoting thelocations of marks to be described below. In this example, the totallength of any given size band 20″ is 6a+2b+c+d for which “a” indicatesthe distance between edges of the indicator markings and hence it isassociated with the % stretching of the elastic band, the distances “b”generally establish the relaxed length of the band, with the locationbetween the two distances “b” denoting a “central” portion 102 of theband 20″, which may or may not be the actual center of the band 20″. Thesegments “c” and “d” are of suitable length to provide for reasonableoverlapping and wrapping around the waist or abdomen, with the centralportion 102 ideally being placed so that it is essentially centered onthe lower back. Example dimensions for multiple sizes of two differentexample implementations for each are also tabulated in Tables 1 and 2.Note that, although Tables 1 and 2 each illustrate four sizes: small,medium, large and extra large, the use of fewer, greater numbers ofsizes or other size ranges are a matter of design choice, the importantaspect being the ability to provide the particular levels ofcompression. In that regard, the values of “a” and “b” are selected sothat the pressure imposed to patients of various waist size iscomparable when the bands are stretched to the specified markings.

TABLE 1 Patient Waist Total Band Number Band Size Size Length of Stripsa b c d h Small 24″~28″ 33.5″ 3  1.25″ 7″ 2″ 10″ 6″   Medium 29″~34″38.5″ 3 1.5″   7.5″   3.5″ 11″ 7″   Large 35″~41″ 45″   3 or 4 2″   8″4″ 13″ 7.5″ Extra Large 42″~48″ 52″   3 or 4 2.5″ 9″ 6″ 13″ 8.5″

TABLE 2 Patient Waist Total Band Number Band Size Size Length of Stripsa b c d h Small 20″~26″ 30 3   1.75″  9″ 3.5″ 12″ 6″ Medium 27″~33″37.5″ 3 3″ 12″ 3.5″ 13″ 7″ Large 34″~40  44.5″ 3 or 4   4.5″ 14″ 3.5″13″   7.5″ Extra Large 41″~47″ 51.5″ 3 or 4 6″ 16″ 3.5″ 14″ 8″

The inner or back surface 20″a of the band 20″ is illustrated in FIG. 9.This is the surface 20″a that contacts the patient when the band 20″ iswrapped about the abdomen or waist of the patient as illustrated inFIG. 1. A trim 22 of suitably stretchable material similar to thatillustrated in FIGS. 2 and 3 may be provided around the edges of theband 20″.

The front or outer surface 20″b of the band 20″ is illustrated in FIG.9A. The outer surface 20″b is the surface of the band 20″ that isexposed when the band is wrapped about the abdomen or waist of a patientas illustrated in FIG. 1. The outer surface 20″b can similarly includeareas 24 a, 24 b such as shown in FIGS. 2A and 3A, that contain eitherthe hooks or loops portion of Velcro® brand hook and loop fasteners. Forsimplicity, those aspects are not shown in FIG. 9 or 9A, as they wouldessentially be the same as shown in FIG. 2A or 3A. The band 20″ alsoincludes multiple indicator markings 92, 94, 96, 98, which will bedescribed in greater detail below. The band 20″ is applied by wrappingit about the abdomen or waist of a patient with the inner surface 20″ain contact with the patient as is shown in FIG. 1. Depending upon theparticular implementation, other types of fasteners can be used with, oras an alternative to, the hook and loop fasteners, for example, any bratype clasps or other type of mating fastener capable of holding thestrips as intended can be used.

The band 20″ also includes narrow, elastic strips. Depending upon theparticular implementation of this band 20″, the discrete elastic stripscan be paired such that there are actually at least three to fiveindividual strips (typically paired and facing opposite directions fromthe center of the band 20″) with one end of each strip having one endthat is sewn or otherwise affixed to the outer surface 20″b of the band20″ and an opposing end that is free from the outer surface.Alternatively, the discrete individual strips may be configured with themiddle of each affixed to band 20″ and both ends of each strip beingfree ends. As shown in FIGS. 9 and 9A, there are six individual strips,three 25″ facing in one direction and the other three 26″ facing in theopposite direction.

A fastener 25″a, 26″a, such as either the complementary hooks or loopsside of a Velcro® brand hook and loop fastener, is connected to eachfree end 100 of each of the elastic strips 25″, 26″ for connection tothe two areas 24 a, 24 b of the band 20″ that is illustrated anddescribed for FIGS. 2A and 3A and present in band 20″, but omitted fromFIG. 9A for simplicity. Each elastic strip 25″, 26″ is typicallyapproximately between one and two inches wide. In the embodimentillustrated in FIGS. 9 and 9A, the band 20″ includes six individualdiscrete elastic strips 25″, 26″ with fasteners on each of the free ends100. The use of at least three elastic strips 25″, 26″ makes the band20″ more closely conform to the body contour of the patient for moreeffective compression of internal organs and provides a greater safetymargin for the patient not to be overly compressed. It is understood,however, that the number of strips shown in FIG. 9 is exemplary and thatthe band 20″ may incorporate a greater number of strips or, in somevariants, a lesser number of elastic strips.

In addition, the band 20″ includes multiple indicator markings 92, 94,96, 98 located successively closer and closer to the ends of the band20″. The indicator markings are placed so as to denote various levels ofcompression. Depending upon the particular implementation, the indicatormarkings may be lines, areas that are contrasted in some manner fromadjacent areas (for example, by ribbons, color, printed markings ordifferent textures), or even differing materials. The first indicatormarking 92, located in this example closest to and on either side of thecentral portion 102 of the band 20″ is a neutral marking that is used todenote an area where the band 20″ will be constrained about the abdomen,but will exert substantially no compressive pressure (i.e., less thanabout 4 mm Hg). Moving in a direction away from the central portion 102of the band 20″, the next indicator marking, on either side of theexterior of the band 20″ in this example, is a “LowComp” marking 94,which is used to denote an area where, when the band 20″ is about theabdomen of a patient and the strips 25″, 26″ are affixed in thisvicinity, a low compressive pressure will be applied, the pressuregenerally being in or about equivalent to pressure within the range ofabout 5 mm Hg to about 12 mm Hg, and nominally centered at a pressure inthe range of between about 8 mm Hg and 10 mm Hg, with the ideal being atabout 10 mm Hg.

Continuing in a direction away from the central portion 102 of the band20″, the next indicator marking is a “MidComp” marking 96, used todenote an area where affixation of the strips 25″, 26″ will causeapplication to the patient of medium compressive pressure, generally inor about equivalent to pressure within the range of about 13 mm Hg toabout 22 mm Hg, and nominally centered at a pressure in the range ofbetween about 15 mm Hg to 20 mm Hg, with the ideal being at about 15 mmHg.

Continuing further in a direction away from the central portion 102 ofthe band 20″, the next indicator marking is a “HiComp” marking 98, whichis used to denote the area where the highest or maximum compressivepressure would be applied to the abdomen, at a value generally in orabout equivalent to pressure within the range of about 23 mm Hg to aboutno more than 30 mm Hg, and nominally centered at a pressure in the rangeof between about 25 mm Hg and 27 mm Hg, with the ideal being at about 25mm Hg.

Alternatively, depending upon the particular materials used, in somecases, the band 20″ may be configured such that, for example, a singlesize band encompasses two or more of the size bands referred to in Table1 above. In such a case, because the neutral mark location would bedifferent with each, the band 20″ may include multiple sets of indicatormarkings and/or appropriately marked, length-adjustable, strips 25″, 26″so that the proper pressure will be applied when the strips 25″, 26″ areaffixed near the specified marks on different sized patients.

Similarly, the band 20″ may be configured with additional or alternativeindicator markings denoting different ranges or levels of compression,the particular style or method of denoting the various compressionlevels being unimportant provided that the LowComp, MidComp and HiComplevels are indicated in some fashion. In addition, in many instances, itmay be undesirable to allow imposition of a compressive pressureequivalent to in excess of about 30 mm Hg. Thus, with most single sizeembodiments, the band 20″ will typically not be configured to allow thestrips 25″, 26″ to be affixed to the band in a location much beyond theHiComp indicator marking or where such excessively high compressionwould be applied.

Advantageously, because narrow strips are used, the patient or thehealth care personnel should be able to more easily pull each strip tothe area of the highest compression force indication marking. Inaddition, by using a greater number and thinner strips than areconventionally used on simple support belts or vests, betterconformation to the waist contour can be achieved so that thecompression can be more uniformly applied to the abdominal organs.

As discussed above, the band 20″ is first wrapped about the abdomen orwaist of a patient to enclose most of the patient's internal abdominalorgans. The band 20″ is then releasably held in place by stretching thestrips 25″, 26″ so as to bring the free ends of the strips 25″, 26″ nearthe indicator marking most appropriate for the desired pressure, thelocation typically being based upon the specific protocol beingfollowed. The fasteners on the end of the strips 25″, 26″ are thenaffixed to the band 20″ in the vicinity of the selected indicatormarking by releasably engaging the fasteners 25″a, 26″a with thecorresponding fasteners located in the areas 24″a and 24″b on the outersurface 20″b of the band. If the strips 25″, 26″ are affixed in the areaof a particular indicator marking and it is necessary or desired tochange the compression to a different level, the free ends of the strips25″, 26″ can easily be disengaged by separating the hook and loopportions from each other, moving the strips 25″, 26″ to the area wherethe desired new compression level will be applied, and re-engaging thestrips to the band 20″ at the new location.

Advantageously, through use of multiple strips 25″, 26″, the instructionfor use can advise the user or health care personnel to stretch thestrips 25″, 26″ closest to the edge of the band 20″ slightly fartherthan the strips closest to the middle (from a height “h” perspective) inorder to allow the band 20″ to better constrain the abdominal organs tobe compressed (i.e., so that a lower percentage of the organs will besqueezed out of the area enclosed by the band 20″).

Optionally, the band 20″ may also include a pouch or pocket 104 intowhich a semi-rigid pad 106 may optionally be inserted. The pad 106 willtypically be about six inches in height and eight inches in width, andmay be contoured to provide for better matching of the contour of theband 20″ with the patient's back and, in some cases, also with the backof the chair that the patient is sitting on or the surface the patientmay be lying on. Advantageously, a set of multiple pads, havingdifferent thicknesses or contour shapes, may be provided so that themost comfortable pad 106 may be selected for insertion into the pouch orpocket 104. In general, consistent with matching the contour of thehuman lower back, in cross section, the pad 106 will be thicker near thecenter and thinner towards its edges. This is shown in FIG. 10 insimplified fashion in the end-on cross section of the pad 106 takenalong line A-A. Alternatively or additionally, the pad 106 can becontoured in a direction perpendicular to line A-A. This is shown in anexample cross section taken at B-B, bearing in mind that any particularpad 106 can be uncontoured, contoured only in the direction shown in theA-A cross section, contoured only in the direction shown in the B-Bcross section, or contoured in some fashion in both cross-sectionaldirections. Note further that the contours shown are each fairly simplefor ease of illustration, however, more sophisticated or physiologicallyaccurate back-conforming contours may be used. Note also that, becausethe pad 106 will add thickness in the center area, at the samestretching of the elastic strips, the waist section around the thickerpart of the pad will experience a higher compression pressure.Advantageously, this can provide benefits for patients with orthostatichypotension (i.e., the development of low blood pressure when standingup from a supine or sitting position) or persons desiring better backsupport.

FIG. 11 illustrates, in simplified form, another alternativenon-inflatable variant band 20″″ which, as shown, includes two strips of23 a, 23 b of fasteners as in FIGS. 3 and 3A, an area 24 containingcomplementary fasteners for mating with the fasteners of strips 23 a, 23b, a set of strips 25′″ similar to the strips 25″ described above thatcan be used to apply compression pressure of different levels byaffixing the fasteners 25″a on their free ends to the complementarymating fasteners within the vicinity of the neutral marking 92, theLowComp marking 94, the MidComp marking 96 or the HiComp marking 98, asdescribed above, each of which is indicated using a different color ortexture. However, as will be seen with this example implementation, theindividual strips 25′″ are affixed at the end opposite the free end andonly extend in one direction. With this example implementation, the band20″″ compression is applied by wrapping the strips 25′″ in only onedirection. In all other respects, the example implementation of FIG. 11is the same as described with respect to the example implementation ofFIGS. 10 and 10A.

Alternative Protocols

Depending upon the particular circumstances, in some cases, it may bedesirable to use a different protocol to treat a hypotensive patient orvascular complications. This is because, although blood pressure can bean indicator of vascular issues, in many instances blood pressure is nota good indicator on whether there is too much blood volume shifted tothe peripheries or the blood volume is too low for proper cardiacfilling producing low cardiac output and low blood pressure. Thus, withthis protocol one or more additional indicators, changes in blooddensity, bioimpedance and hematocrit can be used as additional orindependent means to set the right compression level.

In accordance with the above-described protocols, the protocols specifythat compression pressure is to increase somewhat linearly or stepwiseas the treatment progresses while the vest 10 (with band 20, 20′ or 20″)is being used. The following is an alternative set of protocols thatalso can be used in conjunction with the vest 10 embodiments describedherein to avoid intradialytic hypotension, shock or other vascularcomplications.

These alternative protocols involve monitoring the bioimpedance of theabdominal organs, the density of blood and/or hematocrit.

For the bioimpedance measurement, four electrodes will be placedhorizontally on the patient around the central front portion of thepatient's waist. An electric current is then imposed to the twooutermost electrodes and the voltage of the two inner electrodes ismeasured. The bioimpedance is then ascertained in a similar manner tothat conventionally used for the bioimpedance measurement of the trunk,or similar to that used for bioimpedance measurements made involving thearm or the calf, such as described in Zhu et al., Extracellular fluidredistribution during hemodialysis: bioimpedance measurement and model,Physiol Measure, 29:S491-S501 (2008). Depending upon the particularbioimpedance measurement technique employed, a single frequency and/ormultiple frequencies can be used to assess the impedance of the organsin the waist and to quantify the extracellular fluid volume of thetissue and vasculature and the intracellular fluid of the tissue andvasculature.

In addition, or alternatively, blood density and hematocrit will bemeasured using a conventional blood density or hematocrit monitor orusing any other suitable method of determining fluid density, forexample, using the monitor described in U.S. Pat. No. 7,220,229, theentirety of which is incorporated herein by reference. For the monitorof U.S. Pat. No. 7,220,229, the venous line of the hemodialysis circuitor a by-pass connecting the radial artery to the radial vein of thepatient will be inserted into the slot in the probe of the densitymonitor so that it can measure the blood density as it would the densityof another fluid.

In order to set up for these protocol approaches, in the case ofhemodialysis, the patient will have the vest 10 on before the patient isconnected to the blood lines for the hemodialysis treatment.

Thereafter, continuous or substantially continuous measurement ofbioimpedance, blood density and/or hematocrit begins. Depending upon theparticular implementation, bioimpedance alone, blood density alone,hematocrit alone, or a combination of the three may be used. In hisregard, for simplicity, the protocols will be described in a manner thatallows for either one alone or both and with the various differentimplementations of vest 10. It should be understood and appreciatedhowever that the capability for both measurements is not required, noris limitation to a particular one of the vest 10 embodiments describedherein. If a measurement capability or a particular aspect of a vest orband is not present in the particular implementation, reference to itshould simply be ignored. Thus, reference to X “or” Y relating to aclaim herein should be read as only X if there is no Y capability, onlyY if there is no X capability, and should include both X and Y only ifboth X and Y capabilities are present.

With the foregoing in mind, during the course of treatment, compressionwill be activated with the vest 10 as specified in the protocols below.

If one or more of the following criteria exist:

-   -   a) the average blood pressure drops below about 110 mm Hg,        and/or    -   b) the impedance (or primarily the resistance) shows a decrease        of less than about 5% of its initial value, and/or    -   c) the blood density shows an increase by about 1 g/l (and, more        preferably, by between about 0.5 g/l to about 0.9 g/l), and/or    -   d) the hematocrit of blood shows an increase by about 1% (and,        more preferably, by between about 0.5% to about 0.9%),        then the compression pressure is increased to about 5 mm Hg by,        for example, bladder inflation or stretching and affixing the        elastic strips of the band at about a lower part of the LowComp        marking

When treatment is completed, then this compression pressure will bereleased.

If there is a further measured drop in blood pressure, decrease inimpedance, increase in blood density or increase in hematocrit, thenfurther action may be taken based upon, for example, the followingadditional or alternative protocol.

If the average blood pressure drops below about 100 mm Hg, then thecompression pressure may be increased to about 10 mm Hg by, for example,bladder inflation or stretching and affixing the elastic strips of theband to a higher part of the LowComp marking This is referred to as“Course A.” Once treatment is complete, then the compression pressure isreleased.

If, however, before Course A is complete, the impedance shows nodecrease from its initial value and/or the blood density shows anincrease from its initial value (i.e., before the initiation of CourseA) by about 2 g/l (and, more preferably, by between about 1 g/l to about1.5 g/l) and/or the hematocrit of blood shows an increase from itsinitial value by about 2% (and, more preferably, by between about 1% toabout 1.5%), then the compression pressure may be increased to about 20mm Hg (and, more preferably, to about 15 mm Hg) by, for example, bladderinflation or stretching and affixing the elastic strips of the band atabout the MidComp marking. This is referred to as “Course B.” If thereis no further change, once treatment is complete, then the compressionpressure is released.

However, if, before the completion of Course B, the impedance showsabout a 10% increase from its initial value and/or the blood densityshows an increase from its initial value by about 3 g/l (and, morepreferably, by about 2 g/l, and, ideally between about 1.6 g/l to about2 g/l) and/or hematocrit shows an increase from its initial value byabout 2%, then the compression pressure may be increased to about 25 mmHg (and, more preferably, to about 20 mm Hg) by, for example, bladderinflation or stretching and affixing the elastic strips of the band tothe HiComp marking Again, if there is no further change, once treatmentis complete then the compression pressure is released.

The values specified above for density change, bioimpedance change andhematocrit change are only exemplary. It is expected that, in somecases, a physician or other health care professional will furtheranalyze the bioimpedance, density and hematocrit results of a givenpatient and the patient's quality of life to individualize the valuesand pressures in the above protocols and they may use different readingvalues as triggers, higher levels of compression pressure and/or longertreatment time to care for that patient.

Having described and illustrated the principles of this application byreference to one or more preferred embodiments, it should be apparentthat the preferred embodiment(s) may be modified in arrangement anddetail without departing from the principles disclosed herein and thatit is intended that the application be construed as including all suchmodifications and variations insofar as they come within the spirit andscope of the subject matter disclosed herein.

What is claimed is:
 1. A method of treating a hypotensive patientundergoing a treatment, comprising: elastically constraining the abdomenof the patient while a) concurrently maintaining mobility of thepatient's legs and applying non-pulsating compressive pressure to theinternal organs within the abdomen of the patient according to apredefined protocol with a compression device about the patient'sabdomen, the compression device having at least two discrete elasticstrips and at least two markings, each strip having a free end that isselectively, releasably affixable near any one of the at least twomarkings and each particular marking indicating a different,predetermined compression level from the other markings when the freeends of the strips are releasably affixed near the particular marking,wherein a first of the markings corresponds to a first predeterminedcompression level that will be applied to the abdomen of the patientwhen the respective free ends of the elastic strips are affixed to thecompressive device near the first of the markings, and a second of theat least two markings corresponds to a second predetermined compressionlevel that will be applied to the abdomen of the patient when therespective free ends of the elastic strips are affixed to thecompressive device near the second of the markings, and b) infusing avolume of fluid into the patient's bloodstream, such that pooling ofblood within the patient's abdominal internal organs and distribution ofthe infused volume to the abdominal organs are both reduced.
 2. Themethod according to claim 1, further comprising: adjusting thecompression device from applying the first predetermined compressionlevel to the patient's internal organs within the abdomen to applyingthe second predetermined compression level to the patient's internalorgans within the abdomen in accordance with the predefined protocol. 3.The method according to claim 2, wherein the adjusting comprises movingthe respective free ends of the elastic strips from a location near thefirst of the at least two markings to a location near the second of theat least two markings, and affixing the respective free ends of theelastic strips at the location near the second of the at least twomarkings.
 4. The method according to claim 3, wherein the firstpredetermined compression level is in the range of about 5 mm Hg toabout 12 mm Hg, and the second predetermined compression level is in therange of about 13 mm Hg to about 22 mm Hg.
 5. The method according toclaim 4, wherein the first predetermined compression level is in therange of about 8 mm Hg to about 10 mm Hg, and the second predeterminedcompression level is in the range of about 15 mm Hg to about 20 mm Hg.